1. Field of the Invention
The present invention relates to a peak torque decreasing apparatus for decreasing peak torques generated in an automobile power train.
2. Description of the Related Art
Lightening automobiles for the purpose of improving fuel economy is desirable. Power train members, i.e., a transmission, a propeller shaft, a differential, and an axle shaft, could have their masses and sizes decreased to lighten an automobile.
The masses and sizes of power train members are changed according to the magnitudes of peak torques generated at a rapid start of the automobile (i.e., at sudden clutch connection at a high engine speed), because the power train members are designed to bear the peak torques. Therefore, if the peak torques are decreased, the power train members can be lightened and down-sized.
As a device for cutting peak torques, a torque limiter is known as disclosed in Japanese Utility Model Publication SHO 62-106028. Such a torque limiter cuts torques that are greater than a predetermined torque which is determined by a frictional characteristic of the facing surface of the torque limiter.
However, the predetermined torque of the torque limiter changes according to abrasion of the facing. As a result, a stable torque limiting characteristic cannot be obtained. In addition, once sticking occurs, the torque limiting function does not operate further.